Variable shading

ABSTRACT

In some embodiments, a given frame or picture may have different shading rates. In one embodiment in some areas of the frame or picture the shading rate may be less than once per pixel and in other places it may be once per pixel. An algorithm may be used to determine how the shading rate changes across the frame.

BACKGROUND

This relates generally to graphics processing.

Graphics processors are used to develop images for display on computerdisplays. A graphics pipeline includes a plurality of stages thatdevelop the finished depiction. An image is rendered using rasterizationby sampling different functions and shading. A visibility functiondetermines whether a sample point is inside a triangle. Shadingdetermines what is the color at a certain sample point. Thus, the terms“visibility samples” or “shading samples” are used hereinafter.

In super-sampling anti-aliasing (SSAA), visibility samples are the sameas the shading samples. In multi-sampling anti-aliasing (MSAA), there isa single shading sample per pixel and many visibility samples per pixel.Graphics processors generally support these two anti-aliasing solutions.

BRIEF DESCRIPTION OF THE DRAWINGS

Some embodiments are described with respect to the following figures:

FIG. 1 is a flow chart for one embodiment;

FIG. 2 is a flow chart for another embodiment;

FIG. 3 is a graph of grid cell size with respect to X and Y scalefactors;

FIG. 4 is a depiction of a graphics pipeline according to oneembodiment;

FIG. 5 is a flow chart for one embodiment;

FIG. 6 is a flow chart for another embodiment;

FIG. 7 is a flow chart for still another embodiment;

FIG. 8 is a schematic depiction of one embodiment;

FIG. 9 is a flow chart for one embodiment;

FIG. 10 is a system depiction for one embodiment; and

FIG. 11 is a front elevational view of the embodiment shown in FIG. 10.

DETAILED DESCRIPTION

In some embodiments, a given frame or picture may have different shadingrates. In one embodiment in some areas of the frame or picture theshading rate may be less than once per pixel and in other places it maybe once per pixel and, yet in other places, it may be more than once perpixel. Examples where the shading rate may be reduced include areaswhere there is motion and camera defocus, areas of peripheral blur, andin general, any case where the visibility is reduced anyway.

The concept of MSAA is generalized in one of a variety of differentways. In general, this may be called variable shading rate. One way itcan be generalized is to compute the shading at a rate lower than once apixel, for example, once every 1×2 pixels, 2×1 pixels, 2×2 pixels, 4×2pixels, 2×4 pixels, or 4×4 pixels, to mention some examples. It is alsofeasible to have a fully continuous distribution with two floating pointnumbers, A and B, by giving one shading sample per A×B pixels. Anothervariant is to split the shading into two parts so that one part is doneper pixel or per sample and the other part is done at a slower rate andthen the results are combined.

In modern real-time graphics pipelines, pixel/fragment shading isperformed at a rate of once per geometric primitive per pixel (ifvisible). However, there are many opportunities for reducing pixelshading rates. Such reductions can result in power consumption savingsand in other performance benefits. For example, in cases where motionblur and camera defocus exists, there is an opportunity to havedifferent shading rates in different parts of a frame. When a scene isrendered with motion and camera defocus, regions of the screen mayappear blurred, so the pixel shading rate can be lower in those regionssince they mostly display low frequency content. In cases of peripheralblur, shading rates can be lowered at the periphery of the screen wherehigh frequency details are harder to perceive by the user, at leastassuming the user is focusing attention at the center of the screen.Also, in higher density displays, the shading rate can be loweredwithout significant loss of detail.

While the shading rate can be flexibly lowered, visibility is alsosampled at the full rate to preserve sharp features like edges, in someembodiments.

Referring to FIG. 1, a sequence 10 may be implemented in software,firmware and/or hardware. In software and firmware embodiments, it maybe implemented by computer executed instructions stored in one or morenon-transitory computer readable media, such as magnetic, optical, orsemiconductor storages.

Initially, the rasterizer 21 tests primitives against pixel regions of agiven size, in this example, 2×2 pixel regions 24, called quads. (Pixelregions of other sizes can also be used). The rasterizer traverses thequads in a space filling order, such as the Morton order. If theprimitive covers any of the pixels or samples, in the case ofmulti-sampling, in the quad, as indicated in the depiction labeledcovered quad, the rasterizer sends the quad downstream to a small tilebuffer 16. Early z-culling may be done at 14 in some embodiments.

For a given primitive, the tile buffer may divide the screen into 2N×2Npixel sized tiles, called shading quads, and may store all rasterizedquads that fall inside a single tile as indicated in block 18. A screenaligned shading grid may be evaluated for each 2N×2N tile (block 22).

The size of the grid cell or shading quad may be limited to powers oftwo, as measured in pixels, in some embodiments. For example, the cellsizes may be 1×1, 1×2, 2×1, 4×1, 4×2, 4×4, up to N×N, including 1×N andN×1 and all intermediate configurations.

By controlling the size of the shading grid cell, one can control theshading rate at block 20. That is, the bigger the cell size, the lowerthe shading rate for a tile.

The quads that are stored in the tile buffer are then grouped intoshading quads 26 that consist of groups of adjacent grid cells, such as2×2, adjacent grid cells in one embodiment (block 18). The shading quadsare then shaded and the outputs from the shader are written back to allcovered pixels in the color buffer.

The grid size is evaluated per 2N×2N pixel tile (where N is the size oflargest decoupled pixel within a resized quad and separately for eachgeometric primitive. The “largest decoupled pixel” refers to the size ofthe pixel when the size of shading quad is changed. In one embodimentfour pixels form a quad and each pixel forms one quarter of the quadsize.

The grid size can be controlled by an attribute called the scale factorthat includes a pair of signed values—the scale factor along the X axis,S_(x), and the scale factor along the Y axis, S_(y). The scale factorcan be assigned in various ways. For example, it can be interpolatedfrom vertex attributes or computed from the screen position.

Using signed scale factors can be useful, for example, in the case ofcamera defocus, if a primitive crosses the focus plane. In this case,the vertices of a primitive can be out of focus while the interior ofthe primitive may be in focus. Then one can assign negative scalefactors as attributes for vertices that are in front of the focal planeand positive scale factors as attributes for vertices behind the focalplane and vice versa. For the regions of the primitive that are infocus, the scale factor interpolates to zero and, therefore, maintainshigh shading rates in the in-focus regions.

The scale factors can vary inside a tile, while a single quantized gridcell size is still computed for each tile. This may producediscontinuities in the grid sizes moving from tile-to-tile and canresult in visible grid transitions.

FIG. 2 is a flow chart for a sequence according to one embodiment. Thesequence may be implemented in software, firmware and/or hardware. Insoftware and firmware embodiments, it may be implemented by computedexecuted instructions stored in one or more non-transitory computerreadable media, such as magnetic, optical, or semiconductor storages.

In order to compute the grid size from the scale factor, the scalefactor is first interpolated at the four corners of a 2N×2N tile (block150). If there is a sign change across the four corners of the grid cell(blocks 152 and 154), this indicates a minimum value inside the tile. Inthis case, the minimum possible grid cell spacing is selected, which maytypically be one pixel. Then S_(x) and S_(y) are clamped to a lowerclamping limit (block 156). If there is no sign change, the minimumabsolute value of the scale factor is selected from the four corners(block 158). For some implementations, operations other than the minimummay be used, for instance the average of the absolute values. The quadsize then undergoes an affine mapping (block 160), followed by clampingand quantization (block 162), to determine the grid cell size.

The X and Y scale factors are defined over the real line andindependently mapped to X and Y grid cell size by a function, as shownin FIG. 3, referred to as a scale function, with sides 46 and bottom 44.Other functions may be used in other embodiments. Grid cells smallerthan a single screen space pixel may not be supported, in someembodiments, and, in these cases, the grid cell size is never smallerthan one.

The scale function maps the scale factors that are useful in determininghow the quad size changes and therefore how the shading sampling ratechanges. Specifically, the scale function maps the scale factors to adiscrete pixel size. The scale factors are used to determine the quad'sactual physical screen size. As used herein, a scale function is anyfunction that reduces then increases a pixel region (such as a shadingquad) size in order to change the shading rates.

A value comes from the graphics pipeline as an input to the rasterizerwhich is used to set the scale factor. For example, the input may comefrom a vertex shader, fixed function hardware or it may be implementedat an application program interface level. It may also come from fixedfunction hardware. The input tells the system, for some point on thescreen, or for some primitive, what should be the value for the quadsize. Thus, in FIG. 3, the input value tells what the scale factor wouldbe relative to the flat bottom portion of the scale function. It mapsthe size of the quad into a physical screen size.

In some embodiments, the mapping may be to a physical screen size interms of powers of two. The use of powers of two simplifies the hardwareimplementation.

Advantageously at the transition point, the scale factor is relativelysmall and on either side of the transition point, indicated by thebottom of the scale, the scale factor is larger. Thus as an example,when an object is in focus at zero on the x axis, it may be out of focusat greater and lesser depths. Thus in one embodiment at depths less thanthe plane in which the object is in focus the scale factor may beconsidered negative, and at depths greater than that zero depth level,the scale factor may be positive.

One use case for the scale function may involve an attribute computedper vertex. A triangle may be subject to defocus, with the region infocus at one depth, indicated at zero in the scale function on the xaxis, and the region may be out of focus at lesser and greater depths.The more blurry the triangle is, the less often it may be shaded andhence the scale function provides a tool for making this transition. Thescale function provides a way to linearly interpolate and also to gofrom negative on one side of the focus plane to zero at focus and to apositive number on the other side. Thus, with the scale function, thepixel size is larger on one side of the focus plane, and then it getssmaller at the focus plane, and then it gets larger on the other side ofthe focus plane.

The x axis of the scale function indicates any property interpolatedacross individual triangles in one embodiment. In the example describedabove, the x axis is a measure of depth. But it could be any otherproperty such as the distance across the screen in an example withperipheral blurring. The scale function is one way to change the quadsize but there are other functions and other inputs that can be used toimplement the scale factors in other embodiments.

In another embodiment, the scale function might not indicate aninterpolated property. For example, in the case of peripheral blur, itmay be a value based on the screen coordinates that can be computed by afixed function hardware.

To provide more flexibility, the affine mapping and clamping functionmay be governed by two parameters:float2 ShaderPixelSize=1+max(0,(abs(ScaleFactor)−A)*B);where A controls the width of the flat region 44, while B controls theslope of the left and right ramps 46.

The X and Y components of the grid cell size may be clamped to a finiteinterval [1,M], where M is a power of two between [1,N].

In order to not allow shading quads to overlap regions of the screenthat map to different shading processors, the size of the grid celldetermined by the scale function may be quantized to produce physicalsizes in powers of two (i.e. 1, 2, 4, etc.) in some embodiments. Thisavoids reshading the same quad multiple times. This choice alsominimizes the amount of information exchanged between shadingprocessors. There are at least two methods for quantizing the grid cellsize to a power of two: round and floor. An example pseudo-code for thecase where N=4 is as follows:

//Default Quantized SP Size QuantizedCellSize=1; switch(QuantizationMode) { caseRound: if (ScaleFactor >= 3.f)QuantizedCellSize = 4.f; else if (ScaleFactor > 1.5f) QuantizedCellSize= 2.f; break; caseFloor: if (ScaleFactor >= 4.f) QuantizedCellSize =4.f; else if (ScaleFactor >= 2.f) QuantizedCellSize = 2.f; break;default: break; }

The input value such as an input from the vertex shader, an input fromthe user, an input from an API, or any input from further up thegraphics pipeline, may be used to determine the adjusted quad size. Inone embodiment, the input value may change smoothly and yet the quadsize may not adjust in a similarly smooth fashion. This is because ofthe effects of quantization to factors of two. In some embodiments,these discontinuities that result from the difference between what theinput value dictates should be the quad size and the actual quad size,as quantized, may become visible on the screen.

In some embodiments this screen effect may be compensated for bymodifying the texture level of detail (LOD) to compensate for the errorproduced by the quantization. More specifically, by blurring thetextures by an amount that corresponds to the amount by which the inputvalue suggested quad size differs from the actual quad size, thesediscontinuities can be made relatively hard to see. Thus in someembodiments, an adjustment of the texture coordinates may be madeaccording to the ratio of the desired size that was specified by theinput value from upstream to the actual resulting quantized size.

The scale factors can vary smoothly inside a tile. However, a quantizedgrid cell size may be evaluated once for each tile. This may producediscontinuities in the grid size moving from tile to tile. To compensatethese discontinuities, the texture sample or level of detail calculationmay be enhanced to reflect the actual, un-quantized sampling rate. Thismay be done by scaling the finite differences that are used to computethe level of detail for a given set of texture coordinates:Finite_Difference_new=Finite_Different_Old*(Desired_Cell_Size/Quantized_Cell_Size)

The un-quantized desired cell size may be evaluated at a finegranularity, such as 2×2 pixel regions, and a compensation may beapplied at this fine granularity. This may create a smooth variation inimage detail, masking the discontinuities in grid size.

While a two dimensional example is given, three dimensionalimplementations are also contemplated. In one embodiment, threedimensional spaces may be flattened to two dimensional shading spaces.Three and higher dimensional spaces with decoupling of the visibilityspace from the shading space are also contemplated.

Referring to FIG. 4, when a program running on a host processorinitiates a draw call, the graphics pipeline processes the draw call.One primitive is rasterized at a time. The rasterizer 36 generatesfragments and also generates in one embodiment, a grid cell size. Thegrid cell size is used in the shader core 38. A program memory 34 storesthe instructions for the shader core 38. The shader core outputs theshaded fragments to a frame buffer memory 35.

There are a variety of applications for variable shading rate. Inaccordance with one embodiment, a fixed-rate fall-off may be exploited.A fixed lookup table may be built with a fall-off from the center of thescreen to the edges of the screen. Then a look-up table may have oneshading sample per pixel (SSPP) in the center, and then fall-off assmoothly as the graphics processor allows.

Two examples of the fall-off function from the center towards the edgesis (1) from 1×1 to 1.5×1.5 to 2×2 to 2.5×2.5 to 3.0×3.0 to 3.5×3.5 to4.0×4.0 or (2) from 1×1 to 2×2 to 4×4.

The fall-off distribution may be circular in one embodiment but it mayalso be rectangular to simplify the hardware implementation. Othershapes may also be used.

Any location on the screen or even off the screen can be used as acenter to compute the lookup table index. Then the fall-off function canbe translated across the screen without having to support multiplelookup tables.

With such a fixed rate, one can still let the application programinterface (API) supply some constants to change the shading rate.Assuming that the fixed function shading rate is R, the user can givetwo constants, s and b, where s is a scale and b is the bias. Then thenew shading rate becomes R′=s*R+b. In some applications, includingmobile devices and tablets, this option provides for a simplerimplementation. In some implementations, the center may be the center ofthe screen, while in others it may be set by the programmer an API call.

Referring to FIG. 5, a fixed fall-off sequence 50 may be implemented insoftware, firmware and/or hardware. In software and firmware embodimentsit may be implemented by computer executed instructions stored in one ormore non-transitory computer readable media such as magnetic, optical orsemiconductor storages. For example it may be implemented in oneembodiment in the shader core 38 shown in FIG. 4.

Sequence 50 begins by determining if variable shading rate is opted foras determined in diamond 52. If so, the appropriate lookup table isconsulted as indicated in block 54 in order to obtain the shading rate.Next the center of the depiction is identified as indicated in block 56.This may be supplied in a known predetermined location, from the user orvia default as the center of the depiction, to mention a few examples.Then the appropriate fall-off routine is applied as indicated in block58.

In accordance with another embodiment, a programmable shading rate maybe used. In this case, the programmer handles the shading rate. Theshading rate may be computed per vertex, interpolated over the triangleand truncated or rounded off to the most appropriate shading rate thatthe graphics processor supports.

In the vertex shader, the screen-space distance from the vertexprojected to screen space to the center of the screen is computed. Thenthe center of the screen may be C and the projected vertex position maybe P. The distance may be in a Euclidian space, or a Manhattan distance,as two examples. Then the distance is D and assuming that the maximumdistance from the center to the edge of the screen is L, the vertexshader computes the shading rate R as follows:

vec2 C = vec2(1024,768); //assume screen is 2048x1536 float D =sqrt(dot(P-C,P-C)); //compute Euclidean distance from projected vertexpos to C t=1.0−D/L; //a number between 0.0 (at edges) and 1.0 (center)R=t*R_(max)+(1−t)*R_(min); //compute shading rate, Rwhere R_(max) is the maximum shading rate that is desired in the centerof the screen and R_(min) is the minimum shading rate towards the edgesof the screen. This can also be extended so that the shading rate R isclamped to a minimum or maximum shading rate. The programmable shadingrate can be steered using other facts as well, including objectimportance, surface detail, object focus, object velocity, saliencymaps, surface brightness and contrast, and combinations thereof.

A programmable shading rate sequence 60 shown in FIG. 6 may beimplemented in software, firmware and/or hardware. In software andfirmware embodiments it may be implemented by computer executedinstructions stored in one or more non-transitory computer readablemedia such as magnetic, optical or semiconductor storages. For example,it may be stored in the shader core 38 shown in FIG. 4 in oneembodiment.

The sequence 60 begins by determining if decoupled shading andparticular, programmable variable shading rate, has been selected asdetermined in diamond 62. If so, the screen space distance from thevertex projected to the center of the screen is computed as indicated inblock 64. Then the shading rate is computed as indicated in block 66.Any minimum or maximum clamping may be identified and applied in block68.

Then in block 70 a check determines whether there is any steering suchas steering based on object importance, surface detail, object focus,object velocity, saliency maps, surface brightness and/or contrast. Ifnot, the flow ends and otherwise in block 72 the steering is applied orimplemented.

In accordance with a third embodiment, particularly useful with deviceshaving onboard cameras, a central processing unit or other processortracks where the human eyes are looking on the screen and then feedsthis coordinate data to a vertex shader. In one embodiment computervision algorithms may be used.

Assuming that the computer vision algorithm computes that the viewer islooking at screen space pixel T, in the program above, C can be setequal to T, resulting in the highest shading rates being appliedwherever the viewer is looking with the shading rate falling off withdistance from T. In this case, one may control the value t for exampleby setting t=max (0.0, 1.0−D/L), because D may now be longer than L.Similarly an eye tracking-based shading rate may be used in conjunctionfixed rate fall-off embodiment described previously.

Referring to FIG. 7, an eye gaze sequence 80 may be implemented insoftware, firmware and/or hardware. In software and firmware embodimentsit may be implemented by computer executed instructions stored in one ormore non-transitory computer readable media such as magnetic, optical orsemiconductor storages. In one embodiment it may be implemented in theshader core 38 shown in FIG. 4.

The eye gaze sequence 80, shown in FIG. 7, begins by determining(diamond 82) whether variable shading rate has been selected andparticular, eye gaze based shading. If so, the gaze coordinates areidentified as indicated in block 84. Then in block 86, the shading rateis identified, for example from a stored location or based on a defaultrate. Finally in block 88, the shading rate is applied using the gazecoordinates as the center.

In accordance with another embodiment, the shading rate may be loweredautomatically when a sensor senses that the device is undergoingsufficiently fast movement or rotation. For example in a car game wherethe user rotates a steering wheel, when the steering wheel is rotatedvery quickly to avoid a collision, the shading rate may be reduced byusing variable shading rate or other methods to save power when fastmotion is depicted.

Similarly as another example, when a person is playing a game and ridingin a car over a bumpy road, there may be so much shaking that theshading rate may be reduced to save power without creating a degradationthat, under the circumstances, may be noticed by the user.

Thus referring to FIG. 8, in one embodiment, a processor-based device 90may be a mobile or stationary processor-based device. It may be, in someembodiments, a game device that includes user operable input devicessuch as joy sticks, steering wheels, and/or position sensors to mentionsome examples. Motion sensors 98 may be used to sense the speed ofmotion of a user input device such as a steering wheel, a joy stick orother input devices. Inputs from the motion sensors may be provided tothe processor 92 which may be connected to a display 94 and storage 96.

The motion sensors 98 may be implemented in various ways includingthrough the use of accelerometers. In some cases, some existingprocessor-based devices such as cellular phones already include suchmotion sensors.

In one embodiment, the shading rate may be reduced by a constant factorover the entire screen. This factor may increase proportionately ornon-linearly to the speed of motion with a much lower shading rate withhigher speed.

Another example is to assume that the rotation occurs around the centerof a processor-based device and therefore a fall-off function may beapplied from the center of the screen as described above. In such casethe shading rate may, in one embodiment, be inversely proportional tothe distance from the center of the screen to the tile being renderedand also inversely proportional to the rotation and speed of the device.

With a set of sensors, sensor fusion may be used to compute theapproximate center of rotation of the device. High shading rates may beused at the center of the device and then the shading rate may bereduced based on distance from the center to the tile being rendered andto the rotational speed of the device. Thus the number of shadingsamples per pixel is reduced the higher the speed of the device and thefurther away from the center, the tile is located.

While, in some embodiments, variable shading rates are used, someembodiments may benefit even when variable shading rate is not used. Ifthe sensor signals that the quality of rendering can be reduced, forexample as described above when the rotation speed and distance from therotation center to the tile being rendered is sufficient that imagequality can be lowered, instead of using variable shading rate, thetexture level of detail (LOD) may be changed automatically so that thetexture lookups are done higher up, for example towards the top of themid map pyramid. This increases the hits in the texture cache bylowering the filtered texture quality.

Another option is to reduce the resolution when the sensors signal thatthe device is undergoing a lot of motion. In such cases, resolution maybe reduced by a factor k, in both the x and y directions. For example,assuming that the native resolution is 2048×1536, when sensors indicatethat image quality can be reduced substantially, a driver mayautomatically reduce the resolution to 1024×768. This may be applied toall rendered targets in one embodiment. The final image can then bescaled up to the native resolution of 2048×1536 pixels.

Referring to FIG. 9, a sequence 100 for motion based graphics processingmay be implemented in software, firmware and/or hardware. In softwareand firmware embodiments it may be implemented by computer executedinstructions stored in one or more non-transitory storage media such asmagnetic, optical or semiconductor storage. In some embodiments it maybe implemented using the shader core 38 shown in FIG. 4.

The sequence 100, shown in FIG. 9, begins by checking whether detectedmotion exceeds a threshold as indicated in diamond 102. If so, therendering quality may be reduced or the resolution may be reduced togive two examples as indicated in block 104. The net result may be toreduce power consumption during the period of high motion. When motionhas reduced to a more normal level, then the resolution or renderingquality may be returned to normal as indicated in block 106.

FIG. 10 illustrates an embodiment of a system 700. In embodiments,system 700 may be a media system although system 700 is not limited tothis context. For example, system 700 may be incorporated into apersonal computer (PC), laptop computer, ultra-laptop computer, tablet,touch pad, portable computer, handheld computer, palmtop computer,personal digital assistant (PDA), cellular telephone, combinationcellular telephone/PDA, television, smart device (e.g., smart phone,smart tablet or smart television), mobile Internet device (MID),messaging device, data communication device, and so forth.

In embodiments, system 700 comprises a platform 702 coupled to a display720. Platform 702 may receive content from a content device such ascontent services device(s) 730 or content delivery device(s) 740 orother similar content sources. A navigation controller 750 comprisingone or more navigation features may be used to interact with, forexample, platform 702 and/or display 720. Each of these components isdescribed in more detail below.

In embodiments, platform 702 may comprise any combination of a chipset705, processor 710, memory 712, storage 714, graphics subsystem 715,applications 716 and/or radio 718. Chipset 705 may provideintercommunication among processor 710, memory 712, storage 714,graphics subsystem 715, applications 716 and/or radio 718. For example,chipset 705 may include a storage adapter (not depicted) capable ofproviding intercommunication with storage 714.

Processor 710 may be implemented as Complex Instruction Set Computer(CISC) or Reduced Instruction Set Computer (RISC) processors, x86instruction set compatible processors, multi-core, or any othermicroprocessor or central processing unit (CPU). In embodiments,processor 710 may comprise dual-core processor(s), dual-core mobileprocessor(s), and so forth. The processor may implement the sequences ofFIGS. 5 to 9, together with memory 712.

Memory 712 may be implemented as a volatile memory device such as, butnot limited to, a Random Access Memory (RAM), Dynamic Random AccessMemory (DRAM), or Static RAM (SRAM).

Storage 714 may be implemented as a non-volatile storage device such as,but not limited to, a magnetic disk drive, optical disk drive, tapedrive, an internal storage device, an attached storage device, flashmemory, battery backed-up SDRAM (synchronous DRAM), and/or a networkaccessible storage device. In embodiments, storage 714 may comprisetechnology to increase the storage performance enhanced protection forvaluable digital media when multiple hard drives are included, forexample.

Graphics subsystem 715 may perform processing of images such as still orvideo for display. Graphics subsystem 715 may be a graphics processingunit (GPU) or a visual processing unit (VPU), for example. An analog ordigital interface may be used to communicatively couple graphicssubsystem 715 and display 720. For example, the interface may be any ofa High-Definition Multimedia Interface, DisplayPort, wireless HDMI,and/or wireless HD compliant techniques. Graphics subsystem 715 could beintegrated into processor 710 or chipset 705. Graphics subsystem 715could be a stand-alone card communicatively coupled to chipset 705.

The graphics and/or video processing techniques described herein may beimplemented in various hardware architectures. For example, graphicsand/or video functionality may be integrated within a chipset.Alternatively, a discrete graphics and/or video processor may be used.As still another embodiment, the graphics and/or video functions may beimplemented by a general purpose processor, including a multi-coreprocessor. In a further embodiment, the functions may be implemented ina consumer electronics device.

Radio 718 may include one or more radios capable of transmitting andreceiving signals using various suitable wireless communicationstechniques. Such techniques may involve communications across one ormore wireless networks. Exemplary wireless networks include (but are notlimited to) wireless local area networks (WLANs), wireless personal areanetworks (WPANs), wireless metropolitan area network (WMANs), cellularnetworks, and satellite networks. In communicating across such networks,radio 718 may operate in accordance with one or more applicablestandards in any version.

In embodiments, display 720 may comprise any television type monitor ordisplay. Display 720 may comprise, for example, a computer displayscreen, touch screen display, video monitor, television-like device,and/or a television. Display 720 may be digital and/or analog. Inembodiments, display 720 may be a holographic display. Also, display 720may be a transparent surface that may receive a visual projection. Suchprojections may convey various forms of information, images, and/orobjects. For example, such projections may be a visual overlay for amobile augmented reality (MAR) application. Under the control of one ormore software applications 716, platform 702 may display user interface722 on display 720.

In embodiments, content services device(s) 730 may be hosted by anynational, international and/or independent service and thus accessibleto platform 702 via the Internet, for example. Content servicesdevice(s) 730 may be coupled to platform 702 and/or to display 720.Platform 702 and/or content services device(s) 730 may be coupled to anetwork 760 to communicate (e.g., send and/or receive) media informationto and from network 760. Content delivery device(s) 740 also may becoupled to platform 702 and/or to display 720.

In embodiments, content services device(s) 730 may comprise a cabletelevision box, personal computer, network, telephone, Internet enableddevices or appliance capable of delivering digital information and/orcontent, and any other similar device capable of unidirectionally orbidirectionally communicating content between content providers andplatform 702 and/display 720, via network 760 or directly. It will beappreciated that the content may be communicated unidirectionally and/orbidirectionally to and from any one of the components in system 700 anda content provider via network 760. Examples of content may include anymedia information including, for example, video, music, medical andgaming information, and so forth.

Content services device(s) 730 receives content such as cable televisionprogramming including media information, digital information, and/orother content. Examples of content providers may include any cable orsatellite television or radio or Internet content providers. Theprovided examples are not meant to limit embodiments of the disclosure.

In embodiments, platform 702 may receive control signals from navigationcontroller 750 having one or more navigation features. The navigationfeatures of controller 750 may be used to interact with user interface722, for example. In embodiments, navigation controller 750 may be apointing device that may be a computer hardware component (specificallyhuman interface device) that allows a user to input spatial (e.g.,continuous and multi-dimensional) data into a computer. Many systemssuch as graphical user interfaces (GUI), and televisions and monitorsallow the user to control and provide data to the computer or televisionusing physical gestures, facial expressions, or sounds.

Movements of the navigation features of controller 750 may be echoed ona display (e.g., display 720) by movements of a pointer, cursor, focusring, or other visual indicators displayed on the display. For example,under the control of software applications 716, the navigation featureslocated on navigation controller 750 may be mapped to virtual navigationfeatures displayed on user interface 722, for example. In embodiments,controller 750 may not be a separate component but integrated intoplatform 702 and/or display 720. Embodiments, however, are not limitedto the elements or in the context shown or described herein.

In embodiments, drivers (not shown) may comprise technology to enableusers to instantly turn on and off platform 702 like a television withthe touch of a button after initial boot-up, when enabled, for example.Program logic may allow platform 702 to stream content to media adaptorsor other content services device(s) 730 or content delivery device(s)740 when the platform is turned “off.” In addition, chip set 705 maycomprise hardware and/or software support for 5.1 surround sound audioand/or high definition 7.1 surround sound audio, for example. Driversmay include a graphics driver for integrated graphics platforms. Inembodiments, the graphics driver may comprise a peripheral componentinterconnect (PCI) Express graphics card.

In various embodiments, any one or more of the components shown insystem 700 may be integrated. For example, platform 702 and contentservices device(s) 730 may be integrated, or platform 702 and contentdelivery device(s) 740 may be integrated, or platform 702, contentservices device(s) 730, and content delivery device(s) 740 may beintegrated, for example. In various embodiments, platform 702 anddisplay 720 may be an integrated unit. Display 720 and content servicedevice(s) 730 may be integrated, or display 720 and content deliverydevice(s) 740 may be integrated, for example. These examples are notmeant to limit the disclosure.

In various embodiments, system 700 may be implemented as a wirelesssystem, a wired system, or a combination of both. When implemented as awireless system, system 700 may include components and interfacessuitable for communicating over a wireless shared media, such as one ormore antennas, transmitters, receivers, transceivers, amplifiers,filters, control logic, and so forth. An example of wireless sharedmedia may include portions of a wireless spectrum, such as the RFspectrum and so forth. When implemented as a wired system, system 700may include components and interfaces suitable for communicating overwired communications media, such as input/output (I/O) adapters,physical connectors to connect the I/O adapter with a correspondingwired communications medium, a network interface card (NIC), disccontroller, video controller, audio controller, and so forth. Examplesof wired communications media may include a wire, cable, metal leads,printed circuit board (PCB), backplane, switch fabric, semiconductormaterial, twisted-pair wire, co-axial cable, fiber optics, and so forth.

Platform 702 may establish one or more logical or physical channels tocommunicate information. The information may include media informationand control information. Media information may refer to any datarepresenting content meant for a user. Examples of content may include,for example, data from a voice conversation, videoconference, streamingvideo, electronic mail (“email”) message, voice mail message,alphanumeric symbols, graphics, image, video, text and so forth. Datafrom a voice conversation may be, for example, speech information,silence periods, background noise, comfort noise, tones and so forth.Control information may refer to any data representing commands,instructions or control words meant for an automated system. Forexample, control information may be used to route media informationthrough a system, or instruct a node to process the media information ina predetermined manner. The embodiments, however, are not limited to theelements or in the context shown or described in FIG. 10.

As described above, system 700 may be embodied in varying physicalstyles or form factors. FIG. 11 illustrates embodiments of a small formfactor device 800 in which system 700 may be embodied. In embodiments,for example, device 800 may be implemented as a mobile computing devicehaving wireless capabilities. A mobile computing device may refer to anydevice having a processing system and a mobile power source or supply,such as one or more batteries, for example.

As described above, examples of a mobile computing device may include apersonal computer (PC), laptop computer, ultra-laptop computer, tablet,touch pad, portable computer, handheld computer, palmtop computer,personal digital assistant (PDA), cellular telephone, combinationcellular telephone/PDA, television, smart device (e.g., smart phone,smart tablet or smart television), mobile internet device (MID),messaging device, data communication device, and so forth.

Examples of a mobile computing device also may include computers thatare arranged to be worn by a person, such as a wrist computer, fingercomputer, ring computer, eyeglass computer, belt-clip computer, arm-bandcomputer, shoe computers, clothing computers, and other wearablecomputers. In embodiments, for example, a mobile computing device may beimplemented as a smart phone capable of executing computer applications,as well as voice communications and/or data communications. Althoughsome embodiments may be described with a mobile computing deviceimplemented as a smart phone by way of example, it may be appreciatedthat other embodiments may be implemented using other wireless mobilecomputing devices as well. The embodiments are not limited in thiscontext.

The processor 710 may communicate with a camera 722 and a globalpositioning system sensor 720, in some embodiments. A memory 712,coupled to the processor 710, may store computer readable instructionsfor implementing the sequences shown in FIGS. 5 to 9 in software and/orfirmware embodiments.

As shown in FIG. 11, device 800 may comprise a housing 802, a display804, an input/output (I/O) device 806, and an antenna 808. Device 800also may comprise navigation features 812. Display 804 may comprise anysuitable display unit for displaying information appropriate for amobile computing device. I/O device 806 may comprise any suitable I/Odevice for entering information into a mobile computing device. Examplesfor I/O device 806 may include an alphanumeric keyboard, a numerickeypad, a touch pad, input keys, buttons, switches, rocker switches,microphones, speakers, voice recognition device and software, and soforth. Information also may be entered into device 800 by way ofmicrophone. Such information may be digitized by a voice recognitiondevice. The embodiments are not limited in this context.

Various embodiments may be implemented using hardware elements, softwareelements, or a combination of both. Examples of hardware elements mayinclude processors, microprocessors, circuits, circuit elements (e.g.,transistors, resistors, capacitors, inductors, and so forth), integratedcircuits, application specific integrated circuits (ASIC), programmablelogic devices (PLD), digital signal processors (DSP), field programmablegate array (FPGA), logic gates, registers, semiconductor device, chips,microchips, chip sets, and so forth. Examples of software may includesoftware components, programs, applications, computer programs,application programs, system programs, machine programs, operatingsystem software, middleware, firmware, software modules, routines,subroutines, functions, methods, procedures, software interfaces,application program interfaces (API), instruction sets, computing code,computer code, code segments, computer code segments, words, values,symbols, or any combination thereof. Determining whether an embodimentis implemented using hardware elements and/or software elements may varyin accordance with any number of factors, such as desired computationalrate, power levels, heat tolerances, processing cycle budget, input datarates, output data rates, memory resources, data bus speeds and otherdesign or performance constraints.

The following clauses and/or examples pertain to further embodiments:

One example embodiment may be a method comprising using a processor toalter the shading rate in one region of a picture or frame relative toanother region, and applying an algorithm to determine the rate ofchange of shading rate across the picture or frame. The method may alsoinclude changing the shading rate relative to a center of the picture.The method may also include using a lookup table to determine how tochange the shading rate. The method may also include programmablychanging the shading rate. The method may also include clamping theextent of the rate of change of shading rate. The method may alsoinclude altering the shading rate based on what is depicted in thepicture. The method may also include changing the shading rate based onat least one of object importance, surface detail, object focus, objectvelocity, saliency maps, surface brightness and contrast. The method mayalso include identifying said center using eye tracking. The method mayalso include using a motion sensor to decide whether to change at leastone of shading rate or resolution of the picture. The method may alsoinclude using a motion sensor and a user input device.

In another example embodiment one or more non-transitory computerreadable media storing instructions that, when executed, perform amethod comprising using a processor to alter the shading rate in oneregion of a picture or frame relative to another region, and applying analgorithm to determine the rate of change of shading rate across thepicture or frame. The media may include said method including changingthe shading rate relative to a center of the picture. The media mayinclude said method including using a lookup table to determine how tochange the shading rate. The media may include said method includingprogrammably changing the shading rate. The media may include saidmethod including clamping the extent of the rate of change of shadingrate. The media may include said method including altering the shadingrate based on what is depicted in the picture. The media may includesaid method including changing the shading rate based on at least one ofobject importance, surface detail, object focus, object velocity,saliency maps, surface brightness and contrast. The media may includesaid method including identifying said center using eye tracking. Themedia may include said method including using a motion sensor to decidewhether to change at least one of shading rate or resolution of thepicture. The media may include said method including using a motionsensor and a user input device.

Another example embodiment may be an apparatus comprising a processor toalter the shading rate in one region of a picture or frame relative toanother region and apply an algorithm to determine the rate of change ofshading rate across the picture or frame, and a storage coupled to saidprocessor. The apparatus may include said processor to change theshading rate relative to a center of the picture. The apparatus mayinclude said processor to use a lookup table to determine how to changethe shading rate. The apparatus may include said processor toprogrammably change the shading rate. The apparatus may include saidprocessor to clamp the extent of the rate of change of shading rate. Theapparatus may include said processor to alter the shading rate based onwhat is depicted in the picture. The apparatus may include saidprocessor to change the shading rate based on at least one of objectimportance, surface detail, object focus, object velocity, saliencymaps, surface brightness and contrast. The apparatus may include anoperating system, a battery and firmware and a module to update saidfirmware.

The graphics processing techniques described herein may be implementedin various hardware architectures. For example, graphics functionalitymay be integrated within a chipset. Alternatively, a discrete graphicsprocessor may be used. As still another embodiment, the graphicsfunctions may be implemented by a general purpose processor, including amulticore processor.

References throughout this specification to “one embodiment” or “anembodiment” mean that a particular feature, structure, or characteristicdescribed in connection with the embodiment is included in at least oneimplementation encompassed within the present disclosure. Thus,appearances of the phrase “one embodiment” or “in an embodiment” are notnecessarily referring to the same embodiment. Furthermore, theparticular features, structures, or characteristics may be instituted inother suitable forms other than the particular embodiment illustratedand all such forms may be encompassed within the claims of the presentapplication.

While a limited number of embodiments have been described, those skilledin the art will appreciate numerous modifications and variationstherefrom. It is intended that the appended claims cover all suchmodifications and variations as fall within the true spirit and scope ofthis disclosure.

What is claimed is:
 1. A method comprising: identifying a center regionof a picture or frame; using a processor to alter the shading rate atthe center region of a picture or frame relative to a region surroundingthe center region; and applying an algorithm to determine the shadingrate at each of said regions.
 2. The method of claim 1 including using alookup table to determine how to change the shading rate.
 3. The methodof claim 1 including programmably changing the shading rate.
 4. Themethod of claim 3 including clamping the extent of the rate of change ofshading rate.
 5. The method of claim 3 including altering the shadingrate based on what is depicted in the picture.
 6. The method of claim 5including changing the shading rate based on at least one of objectimportance, surface detail, object focus, object velocity, saliencymaps, surface brightness and contrast.
 7. The method of claim 1including identifying said center using eye tracking.
 8. The method ofclaim 1, including using a motion sensor to decide whether to change atleast one of shading rate or resolution of the picture.
 9. The method ofclaim 8 including using a motion sensor and a user input device.
 10. Oneor more non-transitory computer readable media storing instructionsthat, when executed, perform a method comprising: identifying a centerregion of a picture or frame; using a processor to alter the shadingrate at the center region of a picture or frame relative to a regionsurrounding the center region; and applying an algorithm to determinethe shading rate at each of said regions.
 11. The media of claim 10,said method including using a lookup table to determine how to changethe shading rate.
 12. The media of claim 10, said method includingprogrammably changing the shading rate.
 13. The media of claim 12, saidmethod including clamping the extent of the rate of change of shadingrate.
 14. The media of claim 12, said method including altering theshading rate based on what is depicted in the picture.
 15. The media ofclaim 11, said method including identifying said center using eyetracking.
 16. The media of claim 10, said method including using amotion sensor to decide whether to change at least one of shading rateor resolution of the picture.
 17. The media of claim 16, said methodincluding using a motion sensor and a user input device.
 18. Anapparatus comprising: a processor to identify a center region of apicture or frame, alter the shading rate at the center region of apicture or frame relative to a region surrounding the center region andapply an algorithm to determine the shading rate at each of saidregions; and a storage coupled to said processor.
 19. The apparatus ofclaim 18, said processor to use a lookup table to determine how tochange the shading rate.
 20. The apparatus of claim 18, said processorto programmably change the shading rate.
 21. The apparatus of claim 20,said processor to clamp the extent of the rate of change of shadingrate.
 22. The apparatus of claim 20, said processor to alter the shadingrate based on what is depicted in the picture.
 23. A method comprising:using a processor to change the shading rate relative to a center of thepicture; and applying an algorithm to determine the rate of change ofshading rate across the picture or frame.
 24. The method of claim 23including identifying said center using eye tracking.
 25. The method ofclaim 23 including using a motion sensor to decide whether to change atleast one of shading rate or resolution of the picture.
 26. One or morenon-transitory computer readable media storing instructions that, whenexecuted, perform a method comprising: using a processor to change theshading rate relative to a center of the picture; and applying analgorithm to determine the rate of change of shading rate across thepicture or frame.
 27. The media of claim 26, said method includingidentifying said center using eye tracking.
 28. The media of claim 26,said method including using a motion sensor to decide whether to changeat least one of shading rate or resolution of the picture.
 29. Anapparatus comprising: a processor to use a processor to change theshading rate relative to a center of the picture, apply an algorithm todetermine the rate of change of shading rate across the picture orframe; and a memory coupled to said processor.
 30. The apparatus ofclaim of claim 29, said processor to identify said center using eyetracking.
 31. The apparatus of claim of claim 29, said processor to usea motion sensor to decide whether to change at least one of shading rateor resolution of the picture.
 32. A method comprising: altering theshading rate or resolution at a center of a picture or frame relative toa region; and using a motion sensor to decide whether to change at leastone of shading rate or resolution of the picture.
 33. The method ofclaim 32 including using a motion sensor and a user input device. 34.One or more non-transitory computer readable media storing instructionsthat, when executed, perform a method comprising: altering the shadingrate or resolution at a center of a picture or frame relative to aregion; and using a motion sensor to decide whether to change at leastone of shading rate or resolution of the picture.
 35. The media of claim34, said method including using a motion sensor and a user input device.36. An apparatus comprising: a processor to alter the shading rate orresolution at a center of a picture or frame relative to a region, use amotion sensor to decide whether to change at least one of shading rateor resolution of the picture; and a memory coupled to said processor.37. The apparatus of claim 36, said processor to use a motion sensor anda user input device.